1. Field of the Invention
The present invention relates generally to optical device packaging. More particularly, the present invention relates to an image sensor package with multi-layer RDL, and fabrication method thereof.
2. Description of the Prior Art
In recent year, the solid state image sensor devices have been widely used in mobile phones, automotive and computer industries. However, the shrinkage of the pixel size of the image sensor device and the demand for higher pixel density may have adverse effect on the production yield. For example, the yield may be reduced due to physical contamination during assembly of the camera module. Therefore, packaged semiconductor die and the wafer-level packaging solution have gradually become the acceptable approach to increase yield.
However, one major challenge of the wafer level packaging is the design of the interconnection scheme. Typically, in the choices between top, side and bottom, the bottom contact may be the most popular way to assembly image sensor device because the active side of the image sensor die can operate in coordinate with the assembly direction of the camera modules. There is a growing need in high-density solder pad for high resolution image sensor devices and therefore the through silicon via (TSV) technology that is compatible with solder pad has gained much attention.